First command:

rm replace-packages; for a in /usr/share/pixmaps/*.png; do pkgname="`dpkg -S $a | cut -f1 -d:`"; echo $pkgname >> replace-packages; done


Second command:

for package in `sort -u replace-packages`; do apt-get install --reinstall $package; done

 sudo for package in `sort -u replace-packages`; do apt-get install --reinstall $package; done
bash: syntax error near unexpected token `do'
danny@danny-desktop:~$